Method of producing mixed esters of cellulose



Patented Jan. 22, 1935 I 1,988,532

UNITEDISTATES PATENT, OFFICE- METHOD OF PRODUCING MIXED 'ESTERS OF CELLULOSE David R. Wiggam and John SLTinsley, Kenvil,"

N. J., assignors toHercules Powder Company, Wilmington, DeL, a, corporation of Delaware No Drawing. Application March 30, 1931,

' Serial N0. 526,550

18 Claims. (Cl. 260-401) Our invention relates to a method for the pro-, the method in accordance with our invention duction of mixed. esters of cellulose containing for the production of the new composition of nitrate groups and in addition two or more ormatter, for example, cellulose nitrate, containgarlic acid groups, ing say 2.4% nitrogen, is treated with a mixture of 5 The method embodying our invention involves 2.5 parts of acetic anhydride, 5 partsbutyric 5 reacting cellulose nitrate with two or more oracid and 0.1 part sulphuric acid, the reaction ganic acids. Desirably, the cellulose nitrate is mixture being stirred for three hours at a temsuch that it will contain from about 0.25% to 5.0% perature of 30 C., then being heated to '50". C. of nitrogen and one of the organic acids with for a period ofZhours. At the end of the heatwhich the nitrated cellulose is reacted willberan ing period the mixed ester formed will be found n acid anhydride. Y to be entirely dissolved in the excess of acid. The

The new composition of matter in accordance mixed ester cellulose nitro-aceto-butyrate' will with our invention will be found to possess novel be produced and may be recovered by precipitatand advantageous characteristics, moreparticuing the reaction mixture into, for example, water.

larly, in that, for example, it will be found to The mixedester cellulose nitro+aceto-butyl5 be soluble in a wide range of solvents and inrateflthus prepared will be found to be;a white soluble in such substances as toluol,, ethanol, amorphous substance, soluble in acetone, ethyl etc., etc. and in that it maybe plasticized with lactate, ethyl acetate, butyl acetate, ethylene various plasticizers. In particular, it will be dichloride, etc. and to be insoluble in toluol,

o foundthat from solutions of the mixed ester ethanol, etc. The mixed ester may, where dethere may be deposited clear, strong films on sirable, be plasticized with, for example, aromatic evaporation of the solvent. The compositionwill esters of phosphoric acid, esters of phthalic acid, be found to be highly advantageous forthe prochlorinated diphenyl, .etc., or mixtures and. on duction of photographicfilms, filaments, threads, the evaporation of solvent from a solution there- 5 lacquers, celluloid like substances, etc. of, will deposit clear strong film.

The composition embodying ,our invention may By the method illustrated above, various mixed be produced in accordance with the method emesters in accordance with our invention may be bodying our invention by reacting nitrated celluproduced by the use of other acid anhydridesin lose with at least two organic acids, one of which addition .to acetic; anhydride, or by .the substi-v is an acid anhydride. As has been indicated, the tution of other acid anhydrides .or mixtures 30 nitrated cellulose will desirably contain'from thereof for acetic anhydride, or by the use of 0.25% to 5.0% nitrogen. other acids with or in substitution for-bu'tyric As illustrative, for example, nitrated cellulose acid. Further, by the use of cellulose containing may be reacted with acetic anhydride, propionic varying amounts of nitrogen nd by manipulaa hydr y c a d id t or m xtur tion of the kinds and quantities of acids and an- 35 r and W h butyric acid. p 0pi n c aci hydrides used, compositions having widely vabu y c a ,-P acid, heptoic acid; 6170;, rying properties and "solubilities may be proor mixtures thereof. In effecting the reaction duced I the nitrated cellulose will be admixed with the It will be understood that our invention 40 selectedorganic acids the organic acids pref volves the method for "producingmixed esters of erabty being in excess)? the t fi theoretically cellulose involving broadly the reacting of a nireqmred and the react-Ion facmbated by the trated cellulose withtwo or more organic acids,

plication of heat. Desirably, the reaction W111 be one of which is desirably an anhydride wide Vari effected in the presence of a catalyst and as ation in the method as illustrated herein and, such for example may be used Sulphunc more particularly, variation in the kinds and zinc chloride, benzene sulfonic acid, etc. When the reaction is completed the mixed ester will quantltles of and andanhydnde used bemg be found to be dissolved in the excess of acid templated by 1 as d d mventlonl used and may be readily recovered from solution What We clalm and desire t protect by Letters by precipitation through the medium'of a liq- Patent i 1 5c uid non-solvent for the mixed ester. For pre- 1. The method of pr uc n m ed Cellulo e cipitation of the mixed ester there may be used, esterswhich includes reactin Cellulose n a for example, an organic liquid, as ethyl ether, with an anhydride of an organic acid having the isopropyl ether, ethanol etc. or water. formula CnH2nO2 where n represents a number 65 As a specific example of the carrying out of 2-4 inclusive and an organic acid having the forcontaining from 0.25% to 5.0% of nitrogen with an anhydride of an organic acid having the formula CnH2nO2 where n represents a number, 2-4 inclusive and an organic acid having the formula CnHZnOZ where n represents a number '3-7 inelusive in the presence of a catalyst.

4; The method of producing mixed cellulose.

esters which include reacting cellulose nitrate with an'anhydride of an organic acid having the formula CnHZnOZ where n represents a number 2-4 inclusive andan organic acid having the formula CnHZnOZ wheren represents a number -3-7 inclusive in the presence of sulphuric acid.

5. The method. of producing mixed cellulose esters which includes reacting'cellulose nitrate with an anhydride of 'an' organic acid having the formula CnHZnOz where n represents a number 2-4 inclusive and an organic acid. having the formula CnH2nO2 where n'represents a number 3-7 inclusive, the anhydride being in excess of that required inthe reaction. 9

6. The method of producing mixed cellulose esters which includes reacting cellulose nitrate with an anhydride of an organic'acid having the formula CHI-121102 where. n represents a number 2-4 inclusive and'an organic acid having the formula CnHZnOZ where n representsanumber 3-7 inclusive, precipitating the mixed esters through the medium of a liquid non-solvent of the mixed esters. v i

" 7. The. method of producing mixed'cellulose esters which includes reacting cellulose nitrate containing from 0.25 to.5.0%' of nitrogen with an anhydride of an organic acidhaving the formula CnHZnOZ where n represents a number 2-4 inclusiveand an organic acid havingthe formula CnHZnOZ where n represents a number 3-7' inclusive, the anhydride being in excess of that required in the reaction.

8. The methodof producing mixed cellulose esters which includes reacting cellulose nitrate containing from. 0.25 to 5.0% of nitrogen with an anhydride of an organic acid having the for-'- mula. CnH2nO2 where represents. a number :2-4 inclusive and an organic acid having theformula CnHznoz where n represents a number 3-7 inclusive, precipitatingv the mixed .esters through the medium of a liquid non-solvent of the mixed esters.

9. The method of producing mixed cellulose esters which includes reacting cellulose nitrate containing from 0.25 to 5.0% of nitrogen with an anhydride of an organic acid having the formula CnH2nO2 where n represents a number 2-4 inclusive and an organic acidhaving the formula CnH2xrOg where n representsa; number 3-7 inclusive in the'presence of sulphuric acid.

..10. The method of producing mixed cellulose esters which includes reacting cellulose nitrate with" acetic anhydride'a'nd an organic acid having theformula CnHZnOZ where n represents a number.3-7 inclusive. 1

1'1. 'Th'e method of producing mixed cellulose esters which includes reacting cellulose nitrate containing from 0.25% to 5.0% of nitrogen with acetic anhydride and an organic acid having the formula CnH2nO2 where n represents a number 1 3-7 inclusive, in the presence of a catalyst.

12. The method of producing mixed cellulose esters which includes reacting cellulose nitrate containing from 0.25% to 5.0%, of nitrogen with acetic anhydride and an organic acid having the formula CnH2nO2 where n represents a number 3-7 inclusive, in the presence of sulphuric acid.

13. The method of producing mixed cellulose esters which includes reacting cellulose nitrate with propionic anhydride and an organic acid having the formula CnH2nC2 where n represents a number 3-7 inclusive.

14. The method of producing mixed cellulose esters which includes reacting cellulose nitrate containing from 0.25% to 5.0% of nitrogen with propionic anhydride and an organic acid having the formula CAI-121102 where n represents a number 3-7 inclusive in-the presence of of a catalyst.

15. The method'of producing mixedcellulose esters which includes reacting cellulose nitrate containing from 0.25% to 5.0% of nitrogen with propionic anhydride and'an organic acid having the formula CnH2nO2 where n represents a number. 3-7 inclusive in the presence of sulphuric a'cid.

'16. The method of producing mixed cellulose esters which includes reacting cellulose nitrate with butyric anhydride and an organic acid having the formula CnHznOz' Where n represents a number 3-7 inclusive; "17. The method of producing mixed cellulose esters which includes reacting cellulose nitrate containing from 0.25% to 5.0% of nitrogen with butyric anhydride and an organic acid having the formula CnHZnOZ where n represents a number 3-7 inclusive in the presence of a catalyst.

18L.The method of producing mixed cellulose esters which includes reacting cellulose nitrate containing from 0.25% to 5 .0% of nitrogen with butyric anhydride and an organic acid having the formula CHHZBOZ where .n represents a number 3-7 inclusive in the presence of sulphuric acid.

' JOHNS. TINSLEY.

DAVID R. WIGGAM. 

